A typical axial vane rotary device of the prior art (e.g. U.S. Pat. No. 5,429,084) includes a stator with a cylindrical internal chamber having an annular outer wall and end side walls. Each end wall has an annular cam surface. A rotor is rotatably mounted within the chamber. The rotor has an annular outer wall and a plurality of singularly spaced apart, axially extending slots extending therethrough. A vane is slidably received in each slot. The vanes reciprocate axially and alternatively expand and compress spaces between adjacent vanes and the cam surfaces as the rotor rotates. The cam surfaces have alternating first portions and second portions. The second portions are further from the rotor than the first portions. The first portions of one cam surface are aligned with second portions of another cam surface at the opposite end of the device. The slots extend radially outwards on the rotor to the outer wall thereof. The outer end of each vane slidably engages the annular outer wall of the stator. The outer wall of the stator may have a guide cam and the vanes may have a follower received by the guide cam. The guide cam is shaped to cause the vanes to reciprocate axially with respect to the rotor as the rotor rotates. Each of the vanes may have resiliently biased first seals extending along the inner edge and second seals along end edges thereof
In the above prior art device, the vanes, during rotation of the rotor, move outwardly due to centrifugal force and ride on a film of oil or water on the surface of the annular outer wall. This action is adequate on small axial vane rotary devices or in axial vane rotary devices operating at low speeds, but it is not adequate in large axial vane rotary devices or in axial vane rotary devices operating at high speeds. In such large or high speed axial vane rotary devices, the centrifugal forces build up to such a degree that the annular outer wall cannot withstand these forces and the action of the vanes on the annular outer wall causes excessive wear or damage to these components.
Therefore, a primary objective of the present invention is to provide a means of restraining the vanes from moving outwardly during rotation.
A further objective of the present invention is to provide this restraining action for the vanes in a manner that is independent of the action of the prior art axial vane rotary device.
A still further objective of the present invention is to provide this restraining action on the vanes in a manner that is completely automatic and which does not require any direct control mechanism.
A still further objective of the present invention is to provide this restraining action for the vanes in a manner that will not adversely affect the efficiency or operation of the prior art axial vane rotary device.
A still further objective of the present invention is to provide this restraining action for the vanes in a manner that will not adversely affect the safety or reliability of the prior art axial vane rotary device.
A still further objective of the present invention is to provide this restraining action for the vanes in a manner that will permit economical manufacture and installation in the prior art axial vane rotary device.
These and other objectives will be apparent to those skilled in the art.
The present invention of a vane restraint mechanism for an axial vane rotary mechanism includes a rotor core block which is drilled and tapped to permit the installation of a number of removable rotor end block assemblies. Each of these removable end block assemblies has side portions which are configured to provide a transverse surface parallel to the rotor transverse centerline. Each of the prior art transversely slidable vanes is modified to permit the installation of one or more fixed slide blocks, rotatable rollers, or pivotably mounted rocker assemblies. Each fixed slide block, roller, or rocker assembly bears against the interior surface of these rotor end block assemblies and prevents the rotor from moving outwardly due to centrifugal force.
The fixed mounting of the slide blocks or the rotatable structure of the rollers or rockers of the present invention permit the vanes to operate in the manner similar to the prior art, but prevents any excessive outward travel of the vane that could be caused by centrifugal force.
The attachment of the fixed slide bearing blocks or the rollers or rockers to the vane may be accomplished by any convenient means, but the preferred method is with stainless steel or equivalent pins with stainless steel snap rings.
The use of a rotor core block with a number of individually removable rotor end blocks permits the vane restraint mechanism on each vane to be enclosed completely and allows the seals of the prior art axial vane rotary device to be applied as originally designed at the ends of the vanes and at the surfaces of the annular outer ring. When the vane restraint mechanism is of the two-tier configuration, the removable rotor end blocks are equipped with a removable end panel on two of the rotor end blocks. These removable end panels permit the vane and its attached vane restraint mechanism components to be removed or installed after or while the rotor end blocks are in place on the rotor core block. The removable side panel of the rotor end blocks is not necessary on one-tier vane restraints such as the rockers.
Access for installation or removal of the vanes and vane restraint mechanisms is made possible by means of a removable cover on the annular outer wall and end portions of the casing.